A wiring duct connection device is conventionally used to lead a power supply to a wiring duct 100 as shown in FIG. 9 or to electrically connect wiring ducts together. For example, Japanese Patent. No. 4088441 (JP4088441B) discloses a wiring duct connection device having a structure shown in FIG. 8. The wiring duct connection device includes a connection body 1 inserted into an end portion of a wiring duct 100, a pair of contactors 2 protruding outward from the connection body portion 1, a pair of elongated flat conductor members 200 for resiliently supporting the contactors 2 and a pair terminal blocks 4 electrically connected to the contactors 2 through the conductor members 200. When the connection body 1 is inserted into the wiring duct 100, the contactors 2 are electrically connected to the conductors 110 of the wiring duct 100.
The wiring duct connection device shown in FIG. 8 has a structure in which only one contactor 2 makes contact with each of the conductors 110 of the wiring duct 100. This poses a problem in terms of the contact reliability.
In light of this, Japanese Patent Application Publication No. 2009-283423 (JP2009-283423A) proposes a wiring duct connection device in which a pair of contactors is arranged side by side along a longitudinal direction so as to independently make contact with each of the conductors 110 of the wiring duct 100. Each of the contactors is resiliently supported by an elongated flat conductor member and is electrically connected to a terminal block through the conductor member.
With this wiring duct connection device, the contactors make contact with each of the conductors 110 at two points. This makes it possible to enhance the contact reliability as compared with the wiring duct connection device shown in FIG. 8.
In the wiring duct connection device disclosed in JP2009-283423A, however, each of the contactors arranged side by side along the longitudinal direction needs to be electrically connected to the terminal block through the conductor member. This leads to an increase in the number of electric connection points within the connection body portion, in proportion to which the reliability becomes lower. Moreover, there is a need to prepare a multiple number of contactors because the contactors are arranged side by side along the longitudinal direction. This poses a problem of increased cost.